Small-batch and Print-Your-Own cameras.
Small-batch and Print-Your-Own cameras.
The lens is arguably the most important part of any camera. The lens, after all, focuses the light and determines the field of view that is recorded on the film.
The Kraken 612 is designed to use large format lenses originally manufactured for 4X5 and larger field-, monorail-, and press cameras because the 6cm by 12cm format requires more coverage than most medium format lenses can provide. The 12cm width of the frame is just short of the 12.7cm (5in = 12.7cm) recorded by a 4X5 camera.
In that way, the Kraken 612 and similar cameras that use the format straddle the line between medium format and large format. The main difference is the function of the Kraken 612 is firmly in the medium format camp as focusing is achieved using a rotating helical instead of bellows; it uses readily-available 120 roll film instead of sheet film; and each individual image is conceived and imagined through a viewfinder instead of being previewed on ground glass.
Almost any large format lens with a flange focal distance (FFD–more on this below) between 60mm and 180mm can be used on the Kraken 612. However, there are some limitations.
Early large format cameras did not employ shutters and aperture controls integrated into the lens as early film and other plates had very low sensitivity to light in comparison to today’s film. If you plan on using extremely slow film (ISO lower than 1.0), you could get away with using a lens cap as a shutter.
For the rest of users, a shutter-in-lens arrangement is required.
With lens-in-shutter designs, the shutter has the hardware that mates to the body of the lens. This consists of a cylindrical protrusion at the back of the shutter and a locking ring. The protrusion extends through the lens board and is locked to the lens board by the locking ring.
The lens board on a Kraken 612 sits on the end of a focusing helical. That focusing helical has an inner diameter of 61mm and the shutter threads have to fit inside that.
There are several standard sizes for the hole in the lensboard through which the shutter will mate, the most common being the Copal shutter size numbers:
While these are the most common, there are many different size conventions should you choose a lens that does not use a Copal shutter.
In the printing files for the Kraken 612, you will receive three different lens boards, one each for Copal #00, Copal #0, and Copal #1. Should you need a lens board of another size you have the option of either trimming down one of the provided sizes or requesting a specific size from me at no extra charge. However, most lenses will fit the provided lens boards.
Lens-in-shutter designs have three major components: The front lens element group; the shutter in the middle; the back lens element group. In some lenses, the back element group is too large to fit in an M65 helical. The maximum size the back element group can be is 61mm
It would be wonderful if we could use the same set of numbers to describe the characteristics of lenses as they relate to the format of the frame being recorded but, sadly, that is not the case. Instead, we refer to lenses by focal length (85mm) and relative maximum aperture (f8).
The problem is an 85mm f8 lens is a telephoto on 35mm, normal on 6×7 and wide angle on 4×5. This requires knowing both the format (in the case of the Kraken, the format is 6×12) and the focal length of the lens to determine if a lens-format combination is wide, normal or tele.
I’ve recorded a video that explains the issues involved and how to think of lenses when coupled with the 6×12 format.
The lenses you will be using on the Kraken 612, large format lenses, are constructed differently from the lenses you use on your SLR or the ones that came on your rangefinder. They are lens-in-shutter designs. The video below explains how they work and if you’re new to large format lenses, this will help you quite a bit.
In addition, you may have a lens that has specifications that are difficult to find online. This video will will go about determining the most important measurement for this system, the Flange Focal Distance or FFD. If you don’t know the FFD and your lens is not in the table below, you will need to watch this video on how to measure your FFD.
Film plane to front face of body: 33.5mm
M65 17mm-31mm minmum distance: 17mm
Lens board thickness: 1mm
Total distance film plane to flange: 51.5mm + Actual Lens Cone Measurement.
For instance, if your lens has a flange focal distance of 130mm, your lens cone will be 130mm-51.5mm for a measured length of 78.5mm. This lens cone will be listed as 130mm, The flange focal distance of the lens even though the actual printed length of the cone is 78.5mm.
Man: Manufacturer and Lens Line
Foc Len:Focal Length
Aper: Maximum Aperture
H-FoV: Horizontal Field Of View (H-FoV)
V-FoV: Vertical Field of View (V-FoV)
FFD: Flange Focal Distance (FFD)
Cone: Lens Cone (from the supplied 3D printing files)
Tested: Tested with the Kraken 612?
Notes: Notes about the lens
|35mm SLR lens for Angle of View Comparison||28mm||65°||46°||These are included for angle of view comparison|
|35mm SLR lens for Angle of View Comparison||35mm||54°||37°||These are included for angle of view comparison|
|35mm SLR lens for Angle of View Comparison||50mm||39°||46°||These are included for angle of view comparison|
|35mm SLR lens for Angle of View Comparison||75mm||27°||18°||These are included for angle of view comparison|
|35mm SLR lens for Angle of View Comparison||90mm||23°||15°||These are included for angle of view comparison|
|Fujinon SF||180mm||f5.6||34°||17°||174.5mm||174.5mm||No||I have seen this lens listed as having a FFD of 174.5mm, 176.3mm and 177.5mm PROCEED WITH CAUTION AND BE PREPARED TO PRINT MORE THAN ONE LENS CONE.|
|Fujinon SW||65mm||f8||80°||45°||70mm||70mm||YES||Very Wide|
|Fujinon SW||90mm||f8||63°||33°||99.4mm||100mm||No||Rear elements WILL NOT FIT in M65 Helical. It is recommended to avoid this lens.|
|Fujinon SW||105mm||f8||55°||29°||116.9mm||116mm||No||Rear elements WILL NOT FIT in M65 Helical. It is recommended to avoid this lens.|
|Fujinon SW||120mm||f8||49°||25°||133.5mm||133mm||No||Rear elements WILL NOT FIT in M65 Helical. It is recommended to avoid this lens.|
|Fujinon SWD||75mm||f5.6||72°||39°||84.6mm||84mm||No||Rear elements WILL NOT FIT in M65 Helical. It is recommended to avoid this lens.|
|Fujinon SWD||90mm||f5.6||63°||33°||101.1mm||101mm||No||Rear elements WILL NOT FIT in M65 Helical. It is recommended to avoid this lens.|
|Fujinon W||135mm||f5.6||44°||22°||131.3mm *||131mm||YES||NOTE: The listed flange focal distance of 131.3mm is for a Seiko shutter. FFD and Lens Cone Size in a Copal shutter should be 127mm. However, before you print, it would be good to measure to be sure.|
|Graflex Optar||135mm||f4.7||44°||22°||130mm||130mm||YES||At the time of this writing, this is a very inexpensive lens that produces excellent results.|
|Rodenstock APO-Grandagon||35mm||f4.5||n/a||n/a||43.2mm||NONE||WILL NOT WORK||Flange Focal Distance too short. WILL NOT COVER 4×5|
|Rodenstock APO-Grandagon||45mm||f4.5||101°||62°||55.5mm||NONE||WILL NOT WORK||Flange Focal Distance is too short by 2.5mm|
|Rodenstock APO-Macro-Sionar||120mm||f5.6||49°||25°||235.6mm||NONE||WILL NOT WORK||Flange focal distance too great for lens cone. Printed cone would require printer that can print 190mm height. Contact me if you want to try this lens out.|
|Rodenstock APO-Sionar-S||180mm||f5.6||34°||17°||177mm||177mm||No||Rear barrel may be too big for the M65 helicoid. Make measurements.|
|Rodenstock Ysarex||127mm||f4.7||47°||24°||120mm*||120mm||No||*FFD measured by Nick Lyle|
|Schneider-Kreuznach Angulon||90mm||f6.8||63°||33°||89mm||89mm||Yes. Works well! The 88mm cone is suggested with the addition of 1mm of shims (included in printing files)|
|Schneider-Kreuznach Super Angulon||47mm||f5.6 (XL)||99°||60°||59.1mm||59mm||No|
|Schneider-Kreuznach Super Angulon||58mm||f5.6 (XL)||87°||50°||69.1mm||69mm||No|
|Schneider-Kreuznach Super Angulon||72mm||f5.6 (XL) Coated||75°||41°||81.5mm||81.5mm||No|
|Schneider-Kreuznach Super Angulon||75mm||f5.6||72°||39°||84mm||84mm||No|
|Schneider-Kreuznach Super Angulon||72mm||f5.6 (XL) Multicoated||75°||41°||84mm||84mm||No|
|Schneider-Kreuznach Super Angulon||90mm||f8||63°||33°||98.5mm||98.5mm||No|
|Schneider-Kreuznach Super Angulon||90mm||f5.6 (XL)||63°||33°||102mm||102mm||No|
|Schneider-Kreuznach Super Angulon||90mm||f6.8||63°||33°||102mm||102mm||No|
|Schneider-Kreuznach Super Angulon||120mm||f8||49°||25°||132.5mm||132.5mm||No|
|Schneider-Kreuznach Super Angulon||165mm||f8 Multicoated||37°||19°||179mm||179mm||No|
|Schneider-Kreuznach Super Angulon||165mm||f8||37°||19°||180mm||180mm||No|
|Schneider-Kreuznach Super-Angulon||47mm||f5.6 (MC Multi Coated)||99°||60°||52.2mm||NONE||No||Flange Focal Distance too short|
|Schneider-Kreuznach Super-Angulon||65mm||f5.6 (MC Multi Coated)||80°||45°||72.5mm||72mm||No|
|Schneider-Kreuznach Super-Angulon||75mm||f5.6 (MC Multi Coated)||72°||39°||84.8mm||84mm||No|
|Schneider-Kreuznach Super-Angulon||90mm||f5.6 (MC Multi Coated)||63°||33°||102.7mm||102mm||No|
|Schneider-Kreuznach Super-Angulon||90mm||f8 (MC Multi Coated)||63°||33°||98.8mm||98mm||No|
|Schneider-Kreuznach Super-Angulon||120mm||f8 (MC Multi Coated)||49°||25°||133.1mm||133mm||No|
|Topcon LF Topcor||90mm||f5.6||63°||33°||99.5mm||99.5mm||No|
|Topcon LF Topcor||180mm||f5.6||34°||17°||167mm||167mm||No|
|Topcon LF Topcor||150mm||f5.6||40°||20°||144.2mm||144mm||No|
|Topcon Super Topcor||120mm||f5.6 IC||49°||25°||121.3||119||Yes||This lens is on the Traveling Kraken. This lens ships on a Horseman lens-board that is recessed. You are better using the 119mm lens-cone.|
|Topcon Super Topcor||105mm||f4.5||55°||28°||113mm||112mm||YES||May vignette at wider apertures. Image circle is very close to minimum needed circle for 110mm by 54mm negative. No vignetting has been observed.
The rear lens group barely fits in M65 helical but it DOES fit.
|Topcon Super Topcor||150mm||f5.6||40||20°||130mm||130mm||No|
Note: Angles of view are rounded to the nearest whole degree. Angle of view for 6×12 format is based on a 110mm by 54mm image size, the size of the image produced by the Kraken 612. If you do the math for a 120mm by 60mm image size your results may differ.
Field of view calculations based on PointsInFocus.com website. Go there and check it out, you’ll probably learn something that will help you understand photography better.
Copyright 2020 by Graham Young, all rights reserved | Designed by Graham Young